1. Field of the Invention
The present invention relates to loudspeakers and particularly to loudspeakers using multiple speakers within a single enclosure for high fidelity applications.
2. Description of the Prior Art
Although a number of prior art patents pertain to loudspeakers and the housings of single speakers, none of these prior art patents disclose or suggest the novel features of the present invention; and in particular, the non-rigid mounting of a tweeter within an open cell reticulated polyurethane cartridge so as to position the tweeter 45.degree. off axis with respect to the driver axis of the remaining speakers within the system and further so as to allow placement of the cartridge either 45.degree. to the left or 45.degree. to the right of the remaining speaker driver axes. In addition, none of the prior art patents solely or in combination with each other disclose a loudspeaker enclosure with angular cross-sectional corner posts positioned with respect to the mid-range and high frequency speakers for preventing the majority of off axis mid and high frequency sound waves from emanating into the outside environment, and more particularly, from being reflected into the main radiating pattern of the mid-range and high frequency components waves or back to the sound generating surfaces of the mid-range and high frequency drivers.
The patents developed in a search of the prior art are set forth below in Table I:
TABLE I ______________________________________ Patent No. Inventor Date ______________________________________ U.S. 3,135,349 Lahti 1964 3,155,774 Howell 1964 3,187,832 Broadley 1965 3,345,607 Nelkin et al 1967 3,384,719 Lanzara 1968 3,512,605 McCorkle 1970 3,590,942 Globa 1971 3,684,051 Hopkins 1972 3,708,035 Sotome 1973 3,720,285 Russell et al 1973 3,747,880 Bock 1973 3,824,343 Dahlquist 1974 3,834,486 Tsuge et al 1974 3,867,996 Lou 1975 3,903,989 Bauer 1975 4,006,308 Ponsgen 1977 Australia 251,133 Messer 1964 Canada 697,869 Smolarczyk 1964 France 1,326,414 Hageman 1963 ______________________________________
Thus, although a number of these prior art patents, such as U.S. Pat. Nos. 3,187,832, Broadley; 3,135,349, Lahti; 3,720,285, Russell et al.; 3,867,996, Lou; French Pat. No. 1,326,414; Australian Pat. No. 251,133; and Canadian Pat. No. 697,869 disclose the use of polyurethane or other sound absorbing materials to attenuate unwanted sound waves, none of these prior art patents disclose or suggest the use of angled corner posts to reflect mid and high frequency sound waves striking the posts into a sound absorbing material. Furthermore, although U.S. Pat. No. 3,903,989, Bauer, discloses a loudspeaker having a cabinet with a rotationally adjustable vertically oriented baffle on which additional loudspeaker drivers for generating mid and high frequency signals are supported, this reference does not disclose or suggest the use of an open cell reticulated foam cartridge for a high frequency speaker positionable either 45.degree. to the left or 45.degree. to the right of the axis of the remaining speakers within the loudspeaker.